A coupling grating made in the last high-index layer of a highly reflective multilayer laser output mirror, located at the outside of the laser cavity, induces a significant fall of the reflection coefficient for one of the polarizations. The lasing polarization does not suffer more than 0.1% scattering. The understanding of device operation revealed by experiments shows the way for achieving an i...
View full abstract»

We describe the principle and analyze the operation of an integrated optics directional coupler filter based on coupling between a regular waveguide and one that exhibits electromagnetically induced transparency. Bandwidth length products on the order of 2 pm × mm are obtainable, as an example, using this approach.
View full abstract»

We present what we believe to be the first theoretical study of optical parametric oscillations in isotropic semiconductor microcavities. We have made use of the well-known possibilities of Bragg mirrors with very high reflectivities. The parametric oscillation conditions are derived in a very general and comprehensive way. Design rules are thus defined for optimum nonlinear microcavities. This th...
View full abstract»

We report continuous-wave (CW) operation of a 4.4-THz quantum-cascade laser grown in the GaAs-AlGaAs materials system by molecular beam epitaxy. The device operates at 4 K with a threshold current of 160 mA, and an output power of ∼25 μW. In pulsed mode, the maximum operating temperature is 52 K, with a threshold current of 108 mA at 4 K. CW lasing was achieved by using a small cavity ridge...
View full abstract»

We identify the main reason impeding coherent generation of phonons in solid state - the inherently high density of phonon states. Based on the results of our analysis we formulate a set of conditions that may make phonon lasing practical and point out the most promising mechanism of phonon lasing: LO→LA+TO in InP. We then develop a complete set of phonon laser equations and evaluate the thre...
View full abstract»

Nonlinear dynamics of a semiconductor laser with delayed negative optoelectronic feedback are studied both numerically and experimentally. Mappings of the dynamic states and bifurcation diagrams are compared between a delayed negative optoelectronic feedback system and a delayed positive optoelectronic feedback system. Both systems follow a quasiperiodic route to chaos, where regular pulsing, quas...
View full abstract»

The gain dynamics in erbium-doped fibers (EDFs) with various numerical apertures (NAs) and cutoff wavelengths used in amplifiers employed in wavelength-division-multiplexing (WDM) networks is investigated by using the time-dependent amplifier model. The calculation shows that the transient response at a time immediately after some channels have been dropped depends on the cutoff wavelength, and th...
View full abstract»

A simple physical model is developed for the thermal oxidation process of AlGaAs using the continuity equation. The model is based on the principle of oxidant mass conservation. Theoretical calculations are compared with experimental data to a good agreement. The model is then applied to the study of VCSEL batch fabrication. Several control parameters are discussed including AlGaAs layer thickness...
View full abstract»

A detailed investigation into the dependence of the densities of the principal plasma species in the laser discharge on the buffer-gas operating parameters is reported. Simple expressions for the densities of the Cu, Br, and H species are derived by considering their major mechanisms for production and loss. These predict that the atomic Cu and Br densities are proportional to the HBr mass flow ra...
View full abstract»

The effect of homogeneous upconversion on the performance of an erbium-doped fiber amplifier (EDFA) is analyzed numerically, by means of a set of rate equations model. In particular, the influence of pump power, signal power, and Er3+ concentration on the degradation, due to upconversion, is examined. Forward pumping is considered and amplified spontaneous emission, as well as scatterin...
View full abstract»

A simple technique for simultaneous amplification and compression of ultrashort fundamental solitons is proposed. It is based on an erbium-doped nonlinear amplifying fiber loop mirror. Numerical simulations show that, unlike conventional erbium-doped fiber amplifiers in which nonlinear effects lead to serious degradation of pulse quality, the proposed device performs efficient high-quality amplifi...
View full abstract»

We report a new method for pumping of double-clad, rare-earth-doped fiber sources using diode lasers, diode bars, or fiber-coupled pump sources. In this technique, the pump beam is launched by reflection from a mirror that is embedded in a channel cut into the inner cladding. The mirror may be curved to reduce the divergence of the pump beam, thereby allowing the use of highly divergent pump sourc...
View full abstract»

Aims & Scope

The IEEE Journal of Quantum Electronics is dedicated to the publication of manuscripts reporting novel experimental or theoretical results in the broad field of the science and technology of quantum electronics.